Concrete sandwich panels are used in concrete and precast wall construction. A sandwich panel consists of three layers, commonly called wythes. The two outer layers are concrete with reinforced and the inner layer is comprised of insulating material. The purpose is for the insulating layer to have a high R-factor (measure of thermal resistance) and provide an energy efficient complete wall system in one panel. The standard insulating panel is composed of polystyrene and the like. Ties are used in connection with the insulating panel to mechanically join the insulating layer and the two concrete reinforced panels.
The current invention is directed to a new method for constructing a concrete sandwich panel. Among the improvements is the liquid application of polyurethane foam as the insulating layer during construction. Additionally, a polyethylene channel with basalt fiber rods in wave or square pattern affixed to opposed sides of the channel is employed as a tie during the construction process to join the two concrete panels.